Fuel nozzles



Jan. 19, 1960 w. J. JOHNSYN, JR 2,921,742

FUEL NOZZLES Filed June 16, 1958 29%) M E /q United States Patent FUELNOZZLES Wadsworth I. Johnsyn, Jr., Milton, Mass.

Application June 16, 1958, Serial No; 742,191

3 Claims. (Cl. 239-125) This invention relates to combustion equipment,and ,more particularly to an improved form of fuel nozzle for oilburners and the like. p

This is a continuation in part of my copending application Serial No.643,176, filed February 28, 1957, now abandoned. Application SerialNo.425,843 was a continuation in part of copending application .Serial No.346,101, filed April 1, 1953,.now abandoned. Application Serial No.239,735, filed 'August 1, 1951, now abandoned.

An object of the invention is to providefu'el nozzles having improvedfeatures of construction. Further objects are to provide nozzles whichwill atomize oil efiiciently at a range of capacities, and which areadaptable for use with high pressure units or with those operating atlower oil pressures. Other objects are to provide nozzles ofadvantageous character which will preclude drip of oil when the burnersare not in operation, and additional objects are to provide nozzleswhich are non-clogging or self-cleaning in character.

Other objects of the invention will be apparent to those Tskilled in theart from the disclosures herein made.

In the accompanying drawings, illustrating specific embodiments of theinvention:

Figure 1 is an elevational view, diagrammatic in char- .acter,illustrating the incorporation of a nozzle of this invention in an oilburner unit;

Fig. 2 is a longitudinal section of another modified form of nozzle; 2

Fig 3 is a transverse section on line 33 of Fig.

Fig. 4 is a transverse section on line 4-4 of Fig. 2;

Fig. 5 is a transverse section on line 55 of Fig. 2;

Fig. 5 is also an end view of the forward or head portion of the stern,in association with the valve stem, of the construction shown in Fig. 2;v

Fig. 6 is a longitudinal section of another modified form of nozzle.

In operation, the nozzle is associated with a suitable oil 7 oilpressure conveniently may be. of a value of 100 to 200 pounds per squareinch, or higher, or lower.

In Fig. lthere is indicated generally an oil burner unit wherein anozzle 2 according to this invention is disposed in the housing 4 of ablower 6, and extends into the combustion chamber 8 of a furnace 10.Fuel oil from a storage tank (not shown) is supplied through a pipe 12to a fuel pump 14, from which the oil under constant pressure isdelivered through pipe 16 to the nozzle 2. A re- 7 turn conduit 18,containing a check valve 20, returns unused oil from the nozzle 2 to theintake line 12, whereby the oil supply to the nozzle is at constantpressure regardless of the percentage of fuel capacity at which theburner is being operated. The burner operates at full capacity when thecheck valve 20 is closed, and at progressively decreasing capacities asthe valve 20 is opened.

In the drawings, is shown a form of nozzle construction embodying meansfor accurate and eflicient adjust- 2,921,742 Patented Jan. 19, 1960 2ment of atomization within a desired limited range of operation,together'with other advantageous features of construction.

Nozzle 202 embodies a nozzle tip 204 of known type, to which is securedinternally threaded adjustment sleeve 206. Adjustment body 208 isthreaded into adjustment sleeve 206, and lock nut 210 is threaded on theexterior of adjustment body 208. Oil seal gasket 209, of neoprene or thelike, is disposed between adjustment body 206 and lock nut 210. At itsrearward portion, adjustment body 208 has the internallyjthreadedadapter portion 212 which receives fuel supply pipe 22b. Adjustment body208 also has the return pipe nest portion 214 arranged to receive oilreturn tube .26bj with sliding fit. Threaded into the rearward portionof nozzle tip 204 is retainer sleeve 216, around which is disposed wiremesh oil strainer 218, which is positioned longitudinally between ashoulder of retainer sleeve 216 and the rearward end of nozzle tip 204.Valve stem 220 and stem 222 are movable longitudinally relative to eachother, valve stem 220 being shown as slidable longitudinally withinhollow stem 222. Compression. spring 224 is disposed in the annularspace 219 between valve stem 220 and stem 222, and retainer sleeve 216and nozzle tip 204. The ends of spring 224 bear against shoulders ofvalve stem 22% and stem 222 so that the rearward endof valve stem 2520will bear against the cone-shaped forward end of adjustment body 208,and the forward end of the stem 222 will bear against the cone-shapedinner surface of the nozzle tip 204, to maintain axial alignment ofvalve stem 220 and stem 222 within nozzle tip 204 at any position ofnozzle adjustment.

Adjustment body 208 is provided with longitudinal, symmetrically arrmgedfuel supply passages 226. Adjustment stem 228 extends forwardly of body208 and at its forward endis cone-shaped to provide a bearing surfacefor close cooperation and oil-tight fit with the rearward end of valvestem 220. The forward portion of adjustment body 208 includingadjustment stem 228 is centrally apertured at 232 to provide an oilreturn passage communicating with the interior of oil return tube 26b.

Retainer sleeve 216 is provided with a plurality of symmetricallydisposed radial inlets or feed holes 234 to permit incoming fuel oilpassing (through strainer 218 to enter the annular space 219 containingspring 224 in the movement of the incoming fuel oil forwardly of thenozzle. r

Oil strainer 218 is preferably spaced radially from the outer surface ofretainer sleeve 216-for more effective treatment of the fuel oil passingtherethrough, and for smoother movement of the oil.

Valve stem 220 is provided at its rearward portion with seating flange236 whose rearward surface is shaped. to seat on and cooperate with theadjacent forward end .or bearing surface of adjustment body 208 toprovide an oil-tight seal to prevent interference between oil movingrearwardly through longitudinal passages 238 and 232 toward return tube26b, and incoming oil moving forward- 1y through the annular space 219.The forward surface 237 of flange 236 provides the rearward seatingshoulder for spring 224. At its forward portion, valve stem 220 is solidat the center, and has a reduced forwardly extending valve tip 240, theforward end of which is in axial alignment with orifice 242 of nozzletip 204. From reduced valve tip 240, symmetrically and peripherallydisposed longitudinal slots 243 extend rearwardly to and communicatewith radial drain holes 244, which in turn communicate withlongitudinally extending return passage 238.

Stem 222 has the enlarged head 246 at its forward portion. The rearwardsurface 248 of head 246 proward surface 256 of nozzle tip 204.

vides the forward seating shoulder for spring 224. The

rearwardly of aperture 252.. Grooves 254'inl'the conical portion249extend from the peripheryof head 246 to surface 250. Grooves-254 arenon-radial, and tangential in character. Conical portion 249 bearsagainst and is seatedon the corresponding inner conical for 7 Valve tip2%0 normally extends into. aperture 252 to define annular space 258.Surface 250, valve tip 240, and the adjacent inner forward surface 256of the nozzle tip define whirl. chamber 260.1 Tangential grooves254communicate with annular oil supply passage 219 and whirl chamber 260,which'in turn communicates with orifice partly open, part of the oilsprays out of orifice 242 in the form of a cone, and part of, the oilreturns to return tube 26b by way of annular passages 258 and 253,longitudinal slots 243, radial drain holes 244, and axial returnpassages 238 and 232, and thence to tube'26b.

To produce a desired fixed adjustment of the nozzle, lock nut 210 isreleased, and adjustment sleeve 206 is rotated until orifice 242 isclosed by reason of contact or seating of valve tip 240 on conicalsurface 256 of nozzle tip 204. Then adjustment sleeve 206 is rotated inthe opposite direction until the desired axial spacing of valve tip 240from surface 256 is accomplished, whereupon the lock nut 210 istightened. The nozzle is now in fixed adjustment.

For accuracy and speed in obtaining predetermined adjustment,calibration marks 264 and 266 may be placed on the adjacent surfaces oflock nut 210 and adjustment sleeve 206, respectively. Calibration marks266 may be peripherally spaced to represent predetermined spacingbetween valve tip 240 and conical surface 256 of nozzle tip 204. 7

To adjust the nozzle to predetermined position with the aid ofcalibration marks 264. and 266, lock'nut 210 is released, and adjustmentsleeve 206 is rotated until valve tip 240 is in contact with surface256. The lock nut is turned slightly until mark 264 is opposite one ofthe marks 266. Then adjustment sleeve 286 is rotated in the oppositedirection until the predetermined valve tip opening indicated by thecalibration marks 266 has been accomplished, whereupon lock nut 210 istightened.

The nozzle construction makes possible highly accurate adjustment ofatomization for specific conditions of operation. Furthermore, by theconstruction shown, precise axial alignment of the valvestem and thehead 246 of stem 222 within nozzle tip 204 are maintained at allpositions of nozzle adjustment. v

A compact nozzle construction is shown wherein the means for adjustmentis completely enclosed whereby likelihood of tampering is minimized.

Nozzle tip 204 is identical with that shown in Fig. 6, and the partsthereof are correspondingly numbered. Likewise stem 222, has head 246.Spring 224 and screen 218 are identical'in function with valve stem 220, and in construction varies from valve stem 220 only in a slightlydifferent but essentially equivalent rearward portion. Thus, in; valvestem 220a, va lve tip 240a, longitudinal slots 243a, radial drain holes244a,

tight seal.

and longitudinal return passage 238a are identical with correspondingparts 240, 243, 244 and 238, respectively. At the rearward portion ofvalve stem 220a is flange 270, the forward surface 237a of whichprovides the rearward seating shoulder for. spring 224. The outer edgeof the rearward end 272 of valve stem 220a is utilized for seating thevalve stem as will be described hereinafter.

Adjustment sleeve 274 is threaded into the rearward portion of nozzletip 204. Lock nut 276 is threaded on the exterior of adjustment sleeve274 and bears against the rearward surface of nozzle tip 2 04. Thesleeve 274 is provided witha plurality of symmetrically disposed radialinlets or oil feed holes 277. Strainer 218 is disposed around sleeve274, and its rearward position is limited by flange 278 on said sleeve.The inner diameter of the adjustment sleeve 274 is reduced at portion290 and has cone-shaped seating surface 282 for'therearward end 272 ofvalve stem 220ato provide'an' oil- At its rearward end, sleeve 274 hasthe return pipe nest portion 264 arranged to receive 'oil return tube26c withsliding fit.

Adapter 286 at its forward end is threaded onto the rearward portion ofnozzle tip 204. Fuel supply pipe 22c is threaded into the rearward endof adapter 286;:

In operation, incoming oil enters through oil supply pipe 22c, passesforwardly through annular space 238, through screen 218 and radial inletholes 277, into annular space 21911, through'tangential grooves 254'into whirl chamber 260. The oil whirls tangentially in chamber 260, andwhen valve tip 240 is in the position shown and valve 220a is partlyopen, part of the oil sprays out of orifice 242 in the form of a cone,and part of the oil returns to tube 260 by way of annular passages 258and 253, longitudinal slots 243a, radial drain holes 244a, and axialreturn passages 238a and 290, and thence to tube 260.

To produce a desired fixed adjustment of the nozzle shown adapter 286 isremoved, and lock nut 276 isreleased. Adjustment sleeve 274 is rotatedinto nozzle tip 204 until orifice 242' is closed by reason of seating ofvalve tip 240 on conical surface 256. Then adjustment sleeve 274 isrotated in the opposite direction until the desired axial spacing ofvalve tip 240a from surface 256 is accomplished, whereupon the lock nut276 is tightened. It will be noted that when adapter 286 is replaced,the lock nut is concealed, and likelihood of tampering with theadjustment is minimized. For ease and speed of adjustment, calibrationmarks may be'applied to the lock nut and'other parts. 7

The nozzle construction is compact in character. It will be noted,furthermore, that without the adapter 286, the adjustment sleeve 274together with the nozzle tip 204 and associated parts form aconstruction unit which may be stored by itself, and which requires onlythe addition of the simple adapter 286 for operative connection to afuel s'upplypipe and return tube. It will further be noted that thismodification is admirably suited for permanent adjustment at thefactory.

By way of illustration, in a preferred form of nozzle shown and designedfor a household installation, the orifice 242 may have a diameter ofabout 0.0135 inch, and the diameter of the valve tip 240 may be about0.033 'to 0.040 inch. The ratio of the diameters of orifice 242 andvalve tip 240 is of importance for obtaining optimum operation, and ispreferable about 1 to 3. The inside diameter of the portion of head 246forming the outer boundary of annular space 258 should be such that thecross-sectional area of annular space 258 is equal to the totalcross-sectional area of tangential grooves 254. The larger diameter ofannular space 253 is preferably about twice the larger diameter ofannular space 258. The total cross sectional area of the longitudinalslots 243 is desirably greater than the cross sectional area of annularspace 25s. Thelongitudinalor'axial'dimensioriofannular space 258 ispreferably substantially equal to the transverse width thereof. 7

The valve stem (22%, 22th:) acts to prevent air from entering into thenozzle, and from being drawn back with the oil and contaminating it withair. Said valve stem serves also to adjust the atomization of the oilspray from coarse to extremely fine, while maintaining the oil in veryfine subdivision at all capacities.

By means of the larger annular space 253 rearwardly of the smallerannular space 258, the centrifugal force of the oil moving rearwardlyfrom annular space 258 to space 253 assists in clearing the oil awayfrom the whirl chamber 269 and in maintaining a constant rate ofwhirling in said whirl chamber 266-.

By the construction shown, the returning oil moves rearwardly from whirlchamber 269 without inducing turbulence in said whirl chamber, wherebythe oil being consumed burns in a cone of greatly improved character. Itis further to be noted that the cone of atomized oil is uniformthroughout a wide variation of oil flowing outwardly of the orifice.

It will be understood that various changes and modifications may be madein the nozzle herein disclosed, while still coming within the scope ofthe invention.

Having disclosed my invention, what I claim as new and desire to secureby Letters Patent of the United States is:

1. in a fuel nozzle, in combination, a nozzle tip interiorlycone-shaped, said tip being provided with an orifice centrally of saidcone-shaped surface, a hollow stem axially aligned with said orifice andhaving a head of frusto-conical shape arranged to seat on saidconeshaped tip surface to define a generally cone-shaped whirl chamber,the inclined surface of said head being provided with tangentialgrooves, a valve stem longitudinally slidable within said stem, theforward end of said stem extending into said whirl chamber in axialalignment with said orifice, a sleeve connected to said nozzle tip andhaving an aligning bearing surface in axial alignment with said orifice,the rearward end of said stem bearing on said aligning bearing surfaceof said sleeve, spring means pressing said head and said valve stemagainst their respective bearing surfaces, said sleeve and nozzle tipbeing adjustable longitudinally of each other whereby to vary the axialextension of said valve stem into said whirl chamber, and means forlocking said sleeve and nozzle tip in any position of longitudinaladjustment.

2. In a fuel nozzle, in combination, a nozzle tip interiorlycone-shaped, said tip being provided with an orifice centrally of saidcone-shaped surface, a hollow stem axially aligned with said orifice andhaving a head of frusto-conical shape arranged to seat on saidcone-shaped tip surface to define a generally cone-shaped whirl chamher,the inclined surface of said head being provided with tangentialgrooves, a'valve stem longitudinally slidable within said stem, theforward end of said stem extending into said whirl chamber in axialalignment with said orifice and annularly spaced from the adjacentportions of the head, a sleeve connected to said nozzle tip and havingan aligning bearing surface in axial alignment with said orifice, therearward end of said stem bearing on said aligning bearing surface or"said sleeve, spring means pressing said head and said valve stem againsttheir respective bearing surfaces, passageways for conducting oil fromthe rearward portion of said sleeve to the peripheral portions of saidtangential grooves, and separate passageways for returning oilrearwardly of said valve stem from the annular space adiacent to theforward end of said stern, said sleeve and nozzle tip being adjustablelongitudinally of each other whereby to vary the axial extension of saidvalve stem into said whirl chamber, and means for locksaid sleeve andnozzle tip in any position of longitudinal adjustment.

3. In a fuel nozzle, in combination, a nozzle tip interiorly cone-shapedsaid tip being provided with an orifice centrally of said cone-shapedsurface, a hollow stem axially aligned with said orifice and having ahead of frusto-conical shape arranged to seat on said cone-shaped tipsurface to define a generally cone-shaped whirl chambar, the inclinedsurface of said head being provided with tangential grooves, 21 valvestem longitudinally slideable within said hollow stem, the forward endof said valve stem extending into said whirl chamber in axial alignmentwith said orifice and annularly spaced from the adjacent portions of thehead to define an oil return passage of completely annular characterwhose outer surface is continuous and whose outer diameter is small withrespect to the outer diameter of the base of the whirl chamber, theouter surface of said oil return passage widening directly to asubstantially greater diameter whereby marketedly to increase thecross-sectional area of said annular oil return passage.

References Cited in the file of this patent UNITED STATES PATENTS

